converser.nz

Category: NZTekonverse -> Qgis

  • Upgrading

    The series on how to build a PC from $300 to $3000 is being written as an allusion to my own computer upgrade project I have been working on this week. I took the middle of the road approach to this system and was able to bring the timeline forward after obtaining family support. A…

  • Using Qgis Python Scripting in the NZ Rail Maps Project: 3 – Volumes Formatting

    The third area of Qgis scripting for the NZ Rail Maps project is specifically focused on formatting the Volumes layout images and is used to generate a subtitle displayed in the title bar of each Volumes image. This subtitle informs the user of the year of each aerial image view that is part of the…

  • Using Qgis Python Scripting in the NZ Rail Maps Project: 2 – Volumes Creation

    The second and third aspects of Qgis scripting used in the NZ Rail Maps Project are connected with Volume maps creation. In the Volumes website, static map images are used. Each static image is manually composed, by positioning the map in the composer layout window, and combining the selection of different layers, rotation and zoom…

  • Using Qgis Python Scripting in the NZ Rail Maps Project: 1 – WebMaps

    Good evening. As part of the development of the NZ Rail Maps Project, recently custom Python scripting has been incorporated into the main window GUI and Composer / Layout to speed up processing of various aspects. This is summarised in different sections below. In order to create the content of the NZRM WebMaps site, various…

  • NZRM Webmaps Development Update 2021-03-17 [2]

    Part 1 of this series took a look at some of the technical history of developing the webmaps project. This part will discuss some of the present and future challenges in the NZ Rail Maps Webmaps. As the initial stage of putting all of NZ online in the webmaps is nearing completion, attention will soon…

  • NZRM Webmaps Development Update 2021-03-17 [1]

    One of the features of this blog is that it includes technical posts about the NZ Rail Maps project with which converser.nz blogs are affiliated. These posts are less suitable for a general audience mainly interested in the map content and so are posted on NZTechonverse instead. The NZ Rail Maps live webmaps project is…

  • NZ Rail Maps: Spatialite vs Geopackage

    In the NZ Rail Maps project, I have preferred in recent years to replace shapefiles with databased formats. When using file based dbms (vs client-server) SQlite stands out as a viable alternative that is extremely well supported with an impeccable reputation. There are a number of SQlite based formats of data for GIS layers. Geopackage…

  • NZ Rail Maps: Using Gimp To Georeference Retrolens Aerial Photos [7]: Extracting Mosaic Tiles

    NZ Rail Maps: Using Gimp To Georeference Retrolens Aerial Photos [7]: Extracting Mosaic Tiles

    So I have been trialling the alternative overlay method with more files and have decided to redo all the mosaics for Auckland so far. This is a few days’ work but as there are already some issues with accuracy in some of the more hilly areas or where the embankment is raised, it is going…

  • NZ Rail Maps: Using Gimp To Georeference Retrolens Aerial Photos [6]: Alternate Overlaying Technique

    Today I am going to look at an alternative way of stitching together the source layers. I have to do a set of mosaics for the station of Kamo, which is the northernmost part of Whangarei. From a rail perspective there were two stations there. Just a little south of Kamo there was a coal…

  • NZ Rail Maps: Using Gimp To Georeference Retrolens Aerial Photos [5]: Overlaying Multiple Layers

    NZ Rail Maps: Using Gimp To Georeference Retrolens Aerial Photos [5]: Overlaying Multiple Layers

    So in my last post I showed how to get started in georeferencing with the first overlay. In that post I put the second layer in to show how it would join onto the first layer. The aim of this part is to show how to add additional overlays and how to deal with the…